Modern warships use missiles as offensive and defensive weapons. Vertical Launch Systems (“VLS”) provide a missile firing platform for surface ships and submarines throughout the world. Generally, a VLS is made up of a number of cells, wherein each cell includes at least one individual missile canister. Loaded within each missile canister is an individually firable missile. Within each cell, a variety of different missile designs can be included so as allow for the performance of various missions including for example, anti-aircraft, anti-submarine, strike, naval surface fire support and ballistic missile defense missions. The individual cells are located below a ship's deck providing increased system survivability while reducing the ship's radar cross-section as compared to prior deck mounted systems.
Encapsulating missiles within a canister is desirable because it provides a convenient and safe way to ship, handle and launch the missiles. The operation of the missile within the canister and in firing must be managed due to the potential hazards. In designing a VLS, missiles can be ejected from their individual canisters by ignition within the canister, i.e. a hot launch, or using a non-missile gas followed by ignition of the missile outside the canister, i.e. a cold launch. One advantage of a hot launch system is that the missile is expelled by its own means and thus, an additional ejection mechanism such as, for example, a gas generator and associated structure, is unnecessary. This allows hot launch systems to be smaller and more lightweight as compared to cold launch systems. However, the individual canisters of a hot launch system must be designed to withstand the temperature and pressure associate with igniting the missile within the canister.
Not only must the canisters be designed to withstand the canister flyout pressure during a successful missile egress but in addition, the canister must be able to withstand an unsuccessful missile egress or restrained firing scenario in which the missile is ignited but otherwise fails to exit the canister. The restraint means for the missile, i.e. the means for securing the missile in its associated canister, could fail when the missile was fired. Protection against the hazards associated with such restrained firings was provided in the prior art launchers in the form of a deluge and drain system. Provision for such a system undesirably added to the complexity, cost, maintenance and weight of the launcher. Increased weight is particularly undesirable when the launcher is to be installed aboard a ship.
In order to further reduce both manufacturing costs and cell weight, it would be advantageous to improve upon existing canister design such that the weight of individual canisters can be reduced while still providing exceptional performance in both restrained firing and successful missile egress situations.